Shoe sole

ABSTRACT

Disclosed is a shoe sole having an upwardly sloped front side and an upwardly rear side so that it has a substantially arch-shaped bottom surface, in which a middle sole made of a rigid material is embedded in an outsole. A non-slip sole is attached over the total bottom surface of the outsole. An arch-shaped groove is formed at a center portion of the bottom surface of the outsole. An elliptical stamping cushion is installed in the arch-shaped groove and it is made of a material that is a softer than the outsole. The middle shoe is rounded at a substantially arch shape such that it is corresponding to the shape of the outsole. A rib-shaped reinforcing portion is provided at a middle portion of the middle sole. An uneven surface is provided on an upper surface and a lower surface of the middle sole, respectively. A plurality of through holes are formed through the middle sole and a plurality of cut-away portions are formed at positions of the front side of the middle sole, thereby forming resilient supporting portions.

BACKGROUND OF THE INVENTION

The present invention relates to a shoe sole having an upwardly slopedfront side and an upwardly rear side so that it has a substantiallyarch-shaped bottom surface, in which a middle sole made of a rigidmaterial is embedded in an outsole. More particularly, the presentinvention relates a shoe sole capable of allowing a user to walk in sucha manner that the total portions of the foot can contact the ground insequence with absorbing a shock given by a weight of the user whilewalking, by attaching an elliptical stamping cushion made of a materialthat is a softer than the outsole in an arch-shaped groove formed at arear lower portion of the outsole, and which is capable of allowing thestamping cushion to be rapidly compressed and to rapidly expand so as toalleviate the shock by embedding a plate spring having a circular shapein a main body of the stamping cushion, and which is capable ofpreventing water from penetrating into the main body of the stampingcushion by installing a waterproof cover on an outer surface of thestamping cushion.

A prior art shoe sole structure is shown in Korean Utility ModelRegistration No. 226048. This shoe sole structure includes a resilientmaterial, which has a U-shape and is embedded in a heel portion of anoutsole usually made of polyurethane. If a user putts on a shoe havingthe shoe sole, the weight of the user tends to concentrate in the heelportion while wearing the shoe. Then, the U-shaped resilient materialbecomes slightly constricted and it has a function of supporting theweight of the user, thereby absorbing and alleviating a shock given tothe sole of the foot to a minimum.

One of the principal problems associated with resilient material is thatit cannot firmly being attached to the outsole. The resilient materialcomprises a U-shaped steel plate having a smooth surface. The outsole isusually made of polyurethane and the resilient material is made of thesteel plate, so that they cannot firmly combine with each other.

If a user walks on a street while wearing the shoe, the U-shapedresilient material becomes constricted and restored repeatedly, therebyabsorbing and alleviating a shock given to the sole of the foot. Sincethe outsole and the resilient material are not firmly combined with eachother, a nerve-racking noise may be generated there between at the timeof contacting the ground. In addition, the outsole usually made ofpolyurethane tears easily because of the contact with the U-shapedresilient material made of steel plate.

Another prior art shoe sole structure is shown in Korean PatentRegistration No. 575875. This shoe sole structure includes an outsolehaving a rear side slanted upwards. In this shoe structure, anarch-shaped groove is formed at the center of a lower surface of theoutsole and a rigid middle sole is installed at an upper surface of theoutsole. A cushion material is inserted into the arch-shaped groove. Anon-slip sole is attached onto the total bottom surface of the outsole.Additional cushion materials are attached to front and rear uppersurfaces of the rigid middle sole.

If a user a user walks on a street while wearing the shoe having thisshoe structure, the heel is the first portion of the foot to contact theground. As the step continues and the remainder of the foot contacts theground, the weight of the body is carried forward along the lateral sideof the foot. This type of walking is what we called Masai walking, whichis developed by Karl Mueller. It is well known that this type of walkingis good for health.

One drawback of prior art shoe sole is that a shock given through theheel portion given by the weight of the user while walking on the streetwith wearing the shoe is hardly absorbed and alleviated. In detail,since the total shoe sole is made of some same materials, the shoe mayhave the same capacity for absorbing the shock over the total weightbearing surfaces of the sole. As a result, the shoe having the shoe solestructure as described above does not fully absorb and sufficientlyalleviate the shock given by the weight of the user while walking.

Another drawback of prior art shoe sole is that the user of the shoeinconvenience oneself while walking on the street with wearing the shoe.In detail, since the rigid middle sole is installed at an upper surfaceof the outsole so as to maintain the arch shape of shoe, it gives a feelthat the user steps some hard object while walking.

Accordingly, the present invention has been made to solve theabove-mentioned problems occurring in the prior art, an object of thepresent invention is to provide a shoe sole capable of allowing a userto walk in such a manner that the total portions of the foot can contactthe ground in sequence with absorbing a shock given by a weight of theuser while walking, by attaching an elliptical stamping cushion made ofa material that is a softer than the outsole in an arch-shaped grooveformed at a rear lower portion of the outsole, and which is capable ofcontinuously maintaining the arch shape of the shoe sole so as toproviding the user with safe walking by embedding a middle sole in theoutsole, and which is capable of allowing the stamping cushion to berapidly compressed and to rapidly expand so as to alleviate the shock byembedding a plate spring having a circular shape in a main body of thestamping cushion, and which is capable of preventing water frompenetrating into the main body of the stamping cushion by installing awaterproof cover on an outer surface of the stamping cushion.

SUMMARY OF THE INVENTION

To accomplish the above object, the present invention provides a shoesole, of the type consisting of an outsole having a front side and arear side of a bottom surface thereof, which are sloped upwards, amiddle sole being made of a rigid material and being installed in theoutsole, and a non-slip sole being attached over the total bottomsurface of the outsole,

characterized in that it comprises an arch-shaped groove formed at acenter portion of the bottom surface of the outsole, an ellipticalstamping cushion installed in the arch-shaped groove, the stampingcushion being made of a material that is a softer than the outsole, inwhich the non-slip sole is attached over the total bottom surface of theoutsole and the exposed surface of the stamping cushion, in which themiddle shoe is rounded at a substantially arch shape such that it iscorresponding to the shape of the outsole, in which the thickness of afront end of the middle sole is smaller than those of other portionsthereof, in which a rib-shaped reinforcing portion is provided at amiddle portion of the middle sole, in which an uneven surface isprovided on an upper surface and a lower surface of the middle sole,respectively, in which a plurality of through holes are formed throughthe middle sole and a plurality of cut-away portions are formed atpositions of the front side of the middle sole, which are correspondingto the toe, thereby forming resilient supporting portions.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a shoe sole according to the presentinvention;

FIG. 2 is an exploded sectional view of the shoe sole as shown in FIG.1;

FIG. 3A is a plan view of a middle sole made of a rigid materialaccording to the present invention, and FIG. 3B is a sectional view ofthe middle sole according to the present invention;

FIG. 4 is a sectional view of a stamping cushion according to thepresent invention;

FIG. 5A is a perspective view of a plate spring according to a firstpreferred embodiment of the present invention, FIG. 5B is a sectionalview of the plate spring according to the first preferred embodiment ofthe present invention; and

FIG. 6 is a perspective view of a plate spring according to a secondpreferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the shoe sole according to the present invention will beexplained in more detail with reference to the accompanying drawingsFIGS. 1 to 6.

As shown in FIGS. 1 and 2, the shoe sole comprises an upwardly slopedfront side and an upwardly rear side so that it has a substantiallyarch-shaped bottom surface. A middle sole 30 made of a rigid material isembedded in the outsole 10. An arch-shaped groove 11 is formed at a rearlower portion of the outsole 10. At this time, the position of thearch-shaped groove 11 is corresponding to one's heel. An ellipticalstamping cushion 20 is installed in the arch-shaped groove 11.Preferably, the stamping cushion 20 is made of a material that is asofter than the outsole 10. A non-slip sole 40 is attached over thetotal bottom surface of the outsole 10 and the exposed surface of thestamping cushion 20.

The outsole 10 of the walking shoe according to the present invention ismade of soft foam polyurethane and thereby it has a cushion effect. Asdescribed above, the stamping cushion 20 is made of a material such as acompressed sponge, which is a softer than the outsole 10. Preferably,the softness of the stamping cushion 20 is typically about half thedegree of soft that would do all the outsole 10.

As best seen in FIGS. 2 and 4, the stamping cushion 20 is provided witha waterproof cover 21 for preventing water from penetrating into a mainbody 20 a of the stamping cushion 20. The waterproof cover 21 is made ofa soft material such as a sponge, EVA, etc. and it is attached to anouter surface of the stamping cushion 20. Alternatively, the waterproofcover 21 can comprise a vinyl that may be wound around or applied ontothe total outer surface of the main body 20 a of the stamping cushion20.

A pair of plate springs 22 is embedded in the main body 20 a of thestamping cushion 20. The plate springs 22 are made of an elastic metalplate and are disposed in the main body 20 a in such a manner that theyare opposite to each other. As shown in FIGS. 5A and 5B, the platespring 22 according to the first preferred embodiment of the presentinvention has a circular-shaped tension portion 23 and two resilientportions 25, which are integrally formed with each other. One end of theresilient portion 25 is integrally connected with one side of thecircular-shaped tension portion 23, respectively. This structure widensthe space between two resilient portions 25. A support pin 24 isinserted into an opening of the circular-shaped tension portion 23. Areinforcing portion 26 is added to an outer surface of the resilientportion 25 in a cylindrical embossing pattern thereon, respectively,thereby forming an X-shaped pattern. At positions adjacent to thereinforcing portion 26, a plurality of through holes 27 are formedthrough the resilient port ion 25. A rounded portion 28 is formed at afree end of the resilient portion 25, respectively.

As shown in FIGS. 2 and 3, the middle sole 30 is rounded at asubstantially arch shape such that it is corresponding to the shape ofthe outsole 10. At this time, the thickness of a front end of the middlesole 30 is smaller than those of other portions thereof. A rib-shapedreinforcing portion 33 is provided at a middle portion of the middlesole 30. An uneven surface 31 is provided on an upper surface and alower surface of the middle sole 30, respectively. A plurality ofthrough holes 32 are formed through the middle sole 30. A plurality ofcut-away portions 34 are formed at positions of the front side of themiddle sole 30, which are corresponding to the toe, thereby formingresilient supporting portions 35.

FIG. 6 shows a plate spring 22 a according to the second preferredembodiment of the present invention. The plate springs 22 a are made ofan elastic metal plate. The plate spring 22 a has circular-shapedtension portions 23 and rounded resilient portions 25, which areintegrally formed with each other. Both ends of the resilient portion 25are integrally connected with one side of the circular-shaped tensionportion 23, respectively. The resilient portion 25 extends between thecircular-shaped tensions portions 23. The resilient portion 25 isradially outwardly rounded between the circular-shaped tension portions23. This structure widens the space between two resilient portions 25. Areinforcing portion 26 is added to an outer surface of the resilientportion 25 in a cylindrical embossing pattern thereon, respectively,thereby forming an X-shaped pattern. At positions adjacent to thereinforcing port ion 26, a plurality of through holes 27 are formedthrough the resilient portion 25.

MODE FOR INVENTION

Having described shoe sole according to the preferred embodiment of thepresent invention in detail, the operational relationship of the shoesole can be understood as follows with reference to accompanyingdrawings FIGS. 1 to 6.

In a process for manufacturing a shoe, the shoe sole according to thepresent invention may be attached to a bottom surface of a shoe sheath.If a user walks on a street while wearing the shoe having this shoestructure, the heel is the first portion of the foot to contact theground. That is, if the user walks on a street to Masai's manner ofwalking, the heel portion of the foot contacts the ground earliest ofall.

As shown in FIG. 1, in the shoe sole according to the present invention,a front side and a rear side of the bottom surface of the outsole 10 ofwhich the middle sole 20 is attached to the upper surface of the outsole10 are sloped upwardly, thereby forming a substantially arch shape ofthe shoe.

If a user walks on a street while wearing the shoe having this shoestructure, the heel is the first portion of the foot to contact theground. As the step continues and the remainder of the foot contacts theground, the weight of the body is carried forward along the outercircumferential side of the foot. If the heel leaves the ground, theweight of the body shifts back towards the medial side of the foot.Continuously, if the medial side leaves the ground, the weight of thebody shifts back towards the toe, especially a great toe of the foot.

As shown in FIGS. 1 to 5, the elliptical stamping cushion 20 isinstalled in the arch-shaped groove 11 formed at a rear lower portion ofthe outsole 10, which is corresponding to the hill portion contactingthe ground at first. Since the stamping cushion 20 is made of a materialthat is a softer than the outsole 10 and a pair of plate springs 22 isembedded in the main body 20 a of the stamping cushion 20, the stampingcushion 20 can primarily absorb the shock given by a weight of the userwhile walking.

As the stamping cushion 20 contacts the ground and then it begins to becompressed, the plate springs 22 embedded in the stamping cushion 20 isalso compressed, thereby absorbing the shock given by a weight of theuser while walking. As the stamping cushion 20 leaves the ground, theplate springs 22 restores its original state due to the elastic forcethereof and the stamping cushion 20 restores its original oval shape.

Meanwhile, if the stamping cushion 20 contacts the wet ground and thenit is compressed while walking, water can flow into the main body 20 aof the stamping cushion 20, which is made of a material belonging to thesponge system. Because of the waterproof cover 21 is attached to anouter surface of the stamping cushion 20 or is wound around or appliedonto the total outer surface of the main body 20 a of the stampingcushion 20, it is possible to prevent water from flowing into thestamping cushion 20 while it being compressed.

If water flows into the main body 20 a of the stamping cushion 20, themain body 20 a made of a material belonging to the sponge systemhydrolyzes and thereby it is apt to corrode. Since the waterproof cover21 for preventing water from penetrating into the main body 20 a of thestamping cushion 20 is attached to the total outer surface of thestamping cushion 20, it is possible to prevent water from flowing intothe main body 20 a of the stamping cushion 20 while it being compressed.Accordingly, there is nothing to worry about the corrosion of the mainbody 20 a of the stamping cushion 20.

As described above, the main body 20 a of the stamping cushion 20 ismade of a material belonging to the sponge system and a pair of platesprings 22 embedded in the main body 20 a of the stamping cushion 20 ismade of the steel plate. That is, since the main body 20 a is usuallymade of polyurethane and the plate springs 22 are made of the steelplate, they cannot firmly combine with each other.

To solve this problem, the reinforcing portion 26 is added to the outersurface of the resilient portion 25 in a cylindrical embossing patternthereon, respectively, thereby forming an X-shaped pattern. At positionsadjacent to the reinforcing portion 26, a plurality of through holes 27are formed through the resilient portion 25. A rounded portion 28 isformed at a free end of the resilient portion 25, respectively. Due tothis structure, the plate springs 22 are firmly combined with the mainbody 20 a. Since the outwardly projected portions, the recessed portionsand the through holes 27 in the reinforcing portion 26 are filled withthe materials of the main body 20 a, the materials of the main body 20 aare integrally formed together. In addition, the rounded portion 28 iscombined with the materials of the main body 20 a in such a manner thatit is driven into the materials of the main body 20 a. Consequently, theplate springs 22 are firmly combined with the materials of the main body20 a.

Meanwhile, the support pin 24 is inserted into the opening of thecircular-shaped tension portion 23 of the plate spring 22. If the platespring 22 is continuously compressed and restores its initial state, thecircular-shaped tension portion 23 is apt to cause breakage owing to thefatigue accumulated thereon. At this time, the support pin 24 insertedinto the opening of the circular-shaped tension portion 23 prevents thecircular-shaped tension portion 23 from being compressed and restoringits initial state, thereby minimizing the breakage of thecircular-shaped tension portion 23.

If the plate spring 22 is continuously compressed and restores itsinitial state, the main body 20 a made of soft materials belonging tothe sponge system is apt to cause breakage by means of the distal end ofthe resilient portion 25 made of steel plate. To solve this problem, therounded portion 28 is provided at the distal end of the resilientportion 25 so that it is possible to minimize the breakage of the mainbody 20 a of the plate spring 22.

The plate spring 22 has a relatively wide width of 40 mm or so. If auser walks on a street while wearing the shoe, the plate spring 22 isnot always equally stepped on by means of the heel. Since differentpersons have different manners of walking and the road is not alwayssmooth, the plate spring 22 is unevenly inwardly or outwardly stepped onby means of the heel.

If the plate spring 22 is continuously stepped on to one side by meansof the heel, it is apt to cause transform of the plate spring 22.According to the present invention, the reinforcing portion 26 is addedto the outer surface of the resilient portion 25 in a cylindricalembossing pattern thereon, respectively, thereby forming an X-shapedpattern. Due to this structure, if the plate spring 22 is continuouslystepped on to one side by means of the heel, the reinforcing portion 26supports the plate spring 22 so as to prevent the plate spring 22 frombeing transformed. As a result, the stamping cushion 20 can be equallystepped on and restore its initial state while walking.

Hereinafter, the operational relationship of the middle sole 30 can beunderstood as follows with reference to accompanying drawings FIGS. 1 to3.

The middle sole 30 made of a rigid material is embedded in the outsole10. This middle sole 30 has an arch shape that is substantially the sameas the shape of the outsole 10 so as to continuously maintain the archshape of the outsole 10. The rib-shaped reinforcing portion 33 isprovided at a middle portion of the middle sole 30. This rib-shapedreinforcing portion 33 has a function of preventing the middle portionof the middle sole 30 from unfolding so that the middle portion 30 isnot transformed.

Since the middle sole 30 of the walking shoe according to the presentinvention is made of soft foam polyurethane and is embedded in theoutsole 10, it is possible to attenuate the oppressive feeling and toalleviate the pain applied to the sole of the foot. The shoe sole of thepresent invention has significant advantages over previously known shoesole.

At the joint between the middle sole 30 and the outsole 10, the unevensurface 31 is provided on an upper surface and a lower surface of themiddle sole 30, respectively. In addition, a plurality of through holes32 are formed through the middle sole 30 and a plurality of cut-awayportions 34 are formed at positions of the front side of the middle sole30. Due to this structure, the middle sole 30 is firmly combined withthe outsole 10 so that it is possible to prevent the middle sole 30 frombeing released from the outsole 10.

The pluralities of cut-away portions 34 are formed at positions of thefront side of the middle sole 30, which are corresponding to the toe,thereby forming resilient supporting portions 35. When a user wears theshoes according to the present invention, the toe is corresponding tothe resilient supporting portions 35. At this time, the user feels atease due to operation of the resilient supporting portions 35.

Since the pluralities of cut-away portions 34 are formed at both sidesof the front portion of the middle sole 30, this front portion of themiddle sole 30 can be easily bent so that the user can move the toe witheasy.

Hereinafter, the operational relationship of the plate spring 22 a canbe understood as follows with reference to accompanying drawing FIG. 6.

The plate spring 22 a according to the second embodiment of the presentinvention operates in the same manner as the plate spring 22 accordingto the first embodiment of the present invention, except for partialoperation.

In the plate spring 22 a according to the second preferred embodiment ofthe present invention, the rounded resilient portions 25 are integrallyformed with the circular-shaped tension portions 23 and extend betweenthe circular-shaped tensions portions 23. Between the circular-shapedtensions portions 23, the resilient portions 25 are radially outwardlyrounded and they exhibit an elastic force. Accordingly, the plate spring22 a is formed as a substantially oval shape. Due to this structure,when the plate spring 22 a is continuously compressed and restores itsinitial state, it is possible to prevent the plate spring 22 a frombeing damaged.

In addition, the reinforcing portion 26 is added to an outer surface ofthe resilient portion 25 in a cylindrical embossing pattern thereon,respectively, thereby forming an X-shaped pattern. Accordingly, thedegree of strength of the resilient portion 25 is enhanced due tooperation of the reinforcing portion 26. If the resilient portion 25 ispressed down at its outer side or inner side, it is possible to minimizethe excessive compression of the resilient portion 25 due to operationof the reinforcing portion 26. As a result, it is possible to preventthe user from getting sprained due to operation of the reinforcingportion 26.

In the description of the operation according to the present inventionas described above, it should be noted that, for the sake of clarity andunderstanding of the invention, the detailed description relative to thenon-slip sole 40 attached to the lower surfaces of the outsole 10 andthe stamping cushion 20 is omitted. As shown in FIG. 1, the non-slipsole 40 is attached over the total bottom surface of the outsole 10 andthe exposed surface of the stamping cushion 20 in a state that anelliptical stamping cushion 20 is installed in the arch-shaped groove11.

INDUSTRIAL APPLICABILITY

As described above, the shoe sole according to the present invention iscapable of allowing a user to walk in such a manner that the totalportions of the foot can contact the ground in sequence due to absorbinga shock given by a weight of the user while walking, by attaching anelliptical stamping cushion made of a material that is a softer than theoutsole in an arch-shaped groove formed at a rear lower portion of theoutsole, and which is capable of continuously maintaining the arch shapeof the shoe sole so as to providing the user with safe walking byembedding a middle sole in the outsole, and which is capable of allowingthe stamping cushion to be rapidly compressed and to rapidly expand soas to alleviate the shock by embedding a plate spring having a circularshape in a main body of the stamping cushion.

In addition, the shoe sole according to the present invention is capableof preventing water from penetrating into the main body of the stampingcushion by installing a waterproof cover on an outer surface of thestamping cushion.

While the present invention has been particularly shown and describedwith reference to the particular embodiments thereof, it will beunderstood by those skilled in the art that various changes in form anddetails may be effected therein without departing from the spirit andscope of the invention as defined by the appended claims.

1. A shoe sole comprising an outsole having a front side and a rear sideof a bottom surface thereof, which are sloped upwards, a middle solebeing made of a rigid material and being installed in the outsole, and anon-slip sole being attached over the total bottom surface of theoutsole, wherein an arch-shaped groove is formed at a center portion ofthe bottom surface of the outsole, an elliptical stamping cushion isinstalled in the arch-shaped groove, the stamping cushion being made ofa material that is a softer than the outsole, the non-slip sole isattached over the total bottom surface of the outsole and an exposedsurface of the stamping cushion and the shoe sole further comprises awaterproof cover attached to an outer surface of the stamping cushion.2. A shoe sole according to claim 1, wherein the middle sole is roundedat a substantially arch shape such that it is corresponding to the shapeof the outsole, the thickness of a front end of the middle sole issmaller than the thickness of other portions thereof, a rib-shapedreinforcing portion is provided at a middle portion of the middle sole,an uneven surface is provided on an upper surface and a lower surface ofthe middle sole, respectively, a plurality of through holes are formedthrough the middle sole and a plurality of cut-away portions are formedat positions of the front side of the middle sole, which arecorresponding to the toe, thereby forming resilient supporting portions.3. A shoe sole according to claim 1, further comprising a pair of platesprings that are made of an elastic metal plate and are disposed in thestamping cushion in such a manner that the plate springs are opposite toeach other, each the plate spring having a circular-shaped tensionportion and resilient portions, which are integrally formed with eachother, one end of the resilient portion being integrally connected withone side of the circular-shaped tension portion, respectively, a spacebetween the resilient portions thereby being widened, a support pinbeing inserted into an opening of the circular-shaped tension portion, areinforcing portion being situated on an outer surface of the resilientportion in a cylindrical embossing pattern thereon, respectively,thereby forming an X-shaped pattern, at positions adjacent to thereinforcing portion, a plurality of through holes being formed throughthe resilient portion, and a rounded portion being formed at a free endof the resilient portion, respectively.
 4. A shoe sole according toclaim 2, further comprising a pair of plate springs that are made of anelastic metal plate and are disposed in the stamping cushion in such amanner that the plate springs are opposite to each other, each the platespring having a circular-shaped tension portion and resilient portions,which are integrally formed with each other, one end of the resilientportion being integrally connected with one side of the circular-shapedtension portion, respectively, a space between the resilient portionsthereby being widened, a support pin being inserted into an opening ofthe circular-shaped tension portion, in a reinforcing portion beingsituated on an outer surface of the resilient portion in a cylindricalembossing pattern thereon, respectively, thereby forming an X-shapedpattern, at positions adjacent to the reinforcing portion, a pluralityof through holes being formed through the resilient portion, and arounded portion being formed at a free end of the resilient portion,respectively.
 5. A shoe sole according to claim 1, further comprising apair of plate springs that are made of a metal plate and are disposed inthe stamping cushion in such a manner that the plate springs areopposite to each other, in the plate spring having circular-shapedtension portions and rounded resilient portions, which are integrallyformed with each other, both ends of the resilient portion beingintegrally connected with one side of the circular-shaped tensionportion, respectively, the resilient portion extending between thecircular-shaped tension portions, the resilient portion being radiallyoutwardly rounded between the circular-shaped tension portions, a spacebetween the resilient portions thereby being widened, a reinforcingportion being situated on an outer surface of the resilient portion in acylindrical embossing pattern thereon, respectively, thereby forming anX-shaped pattern, in which at positions adjacent to the reinforcingportion, a plurality of through holes are formed through the resilientportion.
 6. A shoe sole according to claim 2, further comprising a pairof plate springs that are made of a metal plate and are disposed in thestamping cushion in such a manner that the plate springs are opposite toeach other, the plate spring having circular-shaped tension portions androunded resilient portions, which are integrally formed with each other,both ends of the resilient portion being integrally connected with oneside of the circular-shaped tension portion, respectively, the resilientportion extending between the circular-shaped tension portions, theresilient portion being radially outwardly rounded between thecircular-shaped tension portions, a space between the resilient portionsthereby being widened, a reinforcing portion being situated on an outersurface of the resilient portion in a cylindrical embossing patternthereon, respectively, thereby forming an X-shaped pattern, in which atpositions adjacent to the reinforcing portion, a plurality of throughholes are formed through the resilient portion.